Until recently, motherboards have been mounted into personal computers ("PCs") and servers using screws and mounting assemblies that require significant design efforts, assembly time, and perhaps most importantly, a potentially time consuming and complex procedure for replacement of the motherboard mounted within a fully assembled PC or server. Common motherboard mounting techniques currently require large, parallel cable connections for connecting the motherboards to other components within the PC or server. Moreover, mounting techniques often vary from vendor to vendor, so that a motherboard prepared for mounting within a PC or server manufactured by one vendor may not be interchangeable with a motherboard manufactured by a different vendor.
In order to address the above-mentioned motherboard mounting problems, Intel.RTM. has developed a rail-mounting system for motherboards manufactured according to the NLX motherboard specification standard. FIG. 1 shows a detailed view of an NLX rail mounting assembly. Raised brackets 102-107, that together comprise a runner, are punched up through the surface 108 of an enclosure or chassis. A plastic rail 110 is affixed to the lower surface of the motherboard 112 via screws 114-116. In the interest of brevity, the numerical labels used in FIG. 1 will be used again in FIGS. 2 and 3 to label components shown in FIGS. 2 and 3 that are also shown in FIG. 1. FIG. 2 shows a rail positioned prior to mounting onto the runner. The front end of the rail 110 is angled, or tapered, to form a blunt point 202 that is positioned above a first pair of raised brackets 102-103 of the runner. Prior to mounting, the rail 110 is collinear with a central track 204 of the runner and the bottom surface of the rail 110 is coplanar with the surface of the enclosure from which the raised brackets of the runner are punched. The motherboard (not shown in FIGS. 2 and 3) is mounted to the enclosure by sliding the rail 110 affixed to the motherboard into the central track 204 of the runner, so that the rail 110 is held in place by the raised brackets 102-107. FIG. 3 illustrates a rail positioned within the central track of a runner following mounting.
FIGS. 4 and 5 illustrate the use of the NLX motherboard mounting system in a server enclosure. The numerical labels used in FIG. 4 are reused in FIG. 5, for components shown in both figures, for the sake of brevity and clarity. In FIG. 4, a motherboard 402 is positioned for mounting into a server enclosure 404. The server enclosure includes two runners 406 and 408 into which rails 410 and 412, affixed to the underside of the motherboard 402, are slid in order to mount the motherboard 402 securely to the enclosure 404. The motherboard 402 is fully mounted when conductive electrical connectors 414, arranged along the lower edge of the motherboard 402, are snugly fit into a connector receptacle 416.
FIG. 5 shows the motherboard of FIG. 4 mounted within the server enclosure. Once the motherboard 402 has been slid into position, a hinged panel 502 is rotated 90 degrees about two hinges 504 and 506 and snapped into position to form the top of the enclosure 404. This hinged top surface 502 is necessary because, prior to mounting, the motherboard 402 must be positioned, as shown in FIG. 4, with the lower edges of the rails 416 and 418 above the first sets of raised brackets 420 and 422, respectively. Prior to mounting, the top portion of the motherboard 402 extends above the plane of the top of the server enclosure 424-426.
While the NLX rail mounting system, described above in FIGS. 1-5, addresses the above-mentioned problems related to standardization, ease of mounting and replacement, and cableless connection, the necessity of the motherboard to be positioned above the top runner brackets prior to mounting requires either a hinged surface that can be opened to accommodate insertion of the motherboard, as shown in FIGS. 4 and 5, or requires server enclosures having at least once dimension significantly greater than the vertical dimension of the motherboard. However, designers and manufacturers of servers and PCs, in response to consumer demand, strive to keep the size of servers and PCs as small as possible, and strive to minimize manufacturing costs. Design of the hinged top surface of the server enclosure, as shown in FIGS. 4 and 5, adds additional parts and labor costs to the manufacture of the server or PC, and perhaps more importantly, may result in a weakening of the mechanical structure of the enclosure. For these reasons, designers and manufacturers of PCs and servers have recognized the need for a motherboard mounting system compatible with the NLX standard that does not require the motherboard to slide for a significant distance along runners, and that therefore does not require the motherboard to be initially positioned above the top of the runners prior to mounting, as illustrated in FIG. 4.